Analysis of heat transfer at electron beam machine 300 kV/20 mA laboratory

Abstract

Experimental and theoretical analysis of heat transfer at Electron Beam Machine (EBM) Laboratory in Center for Accelerator Science and Technology, National Nuclear Energy Agency (BATAN) are required to understand the heat transfer phenomena. The BATAN’s EBM is a typical 300 kV/20 mA. The room where EBM is based has to be set up according to the laboratory standard to perform at an optimum level. This work aims to evaluate if the installed two air conditioners with a total cooling capacity 160,000 Btu/hr inside the laboratory are sufficient to reach a temperature of 20 °C and atmospheric relative humidity (RH) from 45% to 55%. The laboratory was stacked up with brick, tinted glass window, aluminum door, and rolling door with a total volume of 836 m3. The experiment was performed in cloudy weather for six days from 8:00 a.m. to 4:00 p.m. and the data of temperatures at each spot were taken every one hour. There were three conditions of this experiment, air conditioner running with laboratory lamps set to be off, air conditioner running with laboratory lamps set to be on, and air conditioner running with laboratory lamps set to be on and insulating 10.5 m2 rolling door with 50 mm Styrofoam respectively every two days. The result showed that for the first condition, the average temperature of laboratory and atmospheric relative humidity (RH) was 22.5 °C and 59%, respectively. In the second condition, the average temperature of laboratory and atmospheric relative humidity (RH) was 21.9 °C and 65% respectively, whereas, in the third condition, the average temperature of laboratory and atmospheric relative humidity (RH) were 19.9 °C and 49% respectively. This result indicates that adding thermal insulation such as Styrofoam inside the building helps the air conditioners to reach its targeted temperature and RH.